Moisture extracting press



May 30, 1961 o. BRAUN 2,986,082

MOISTURE ExTRAcTING PREss Filed oct. 22, 1958 2 Sheets-sheet 1 May 30, 1961 o. BRAUN 2,986,082

MOISTURE EXTRACTING PRESS Filed Oct. 22, 1958 2 Sheets-Sheet, 2

United States Patent O MOISTURE EXTRACTING PRESS Oskar Braun, Bensheim-Auerbach an der Bergstrasse, Germany, assigner to Josef Wllmes, Bensheim an der Bergstrasse, Germany Filed Oct. 22, 1958, Ser. No. 768,986

Claims priority, application Germany Oct. 30, 1957 5 Claims. (Cl. 10D-50) The present invention relates to presses for extracting moisture from a moisture-containing material, and more particularly to presses with rotatable drums mounted on horizontal shaft means and reciprocable press platens. Reciprocation of the press platens is effected by providing a threaded bearing engaging a threaded shaft, the threaded shaft and bearing constituting two axially reciprocable elements and the reciprocable press platen being xedly connected to one of these elements whereby the platen may be reciprocated in relation to the other element by turning one of the elements.

When the threaded shaft extends into the drums defining the press chamber, it will be corroded by most moisture-containing materials, such as fruit mash, if the shaft consists, as is usual, of corrosive ferrous alloys or iron. In addition, only odorand tasteless lubricants can be used on the threads if edible materials are pressed and the effect of such a lubricant will be limited because it will be rapidly removed by the pressure of the material.

ln an effort to overcome these disadvantages, special sleeves have been suggested to protect the threaded shaft, but, in addition to the additional expense, this solution has encountered many operating difficulties.

lt is the principal object of the present invention to overcome the disadvantage of presses of this type by eliminating all threaded shafts from the interior of the press chamber. If any shaft portion extends into the press chamber, such a shaft portion is smooth, according to the invention, so that it may readily be provided with a corrosion-resistant lacquer or metallic coating, or an inexpensive protective sleeve which may be hermetically sealed to the press platen. Also, such a smooth shaft portion will provide a good gliding surface for a press platen and its sealing gasket during reciprocation of the platen on this shaft portion. Since the threaded shaft portion is outside the press chamber, it may be lubricated with conventional lubricants without regard to their odor or taste.

The above and other objects and advantages are accomplished in accordance with the invention by providing a press with a rotatable perforate drum defining a press chamber, substantially horizontal shaft means rotatably supporting the drum and having a threaded end portion totally outside the drum, two press platens mounted on the shaft means and forming drum bottoms tol close the press chamber, either one or both of the press pl atens being mounted for reciprocatory movement on the shaft means, a threaded bearing engaging and supporting the threaded end portion of the shaft, the reciprocatory press platen being fixedly connected either to the threaded shaft portion or the threaded bearing, and follower means interconnecting the drum` and each reciprocatory platen whereby such platen is rotated upon rotation of and with the drum.

`In accordance with one embodiment of the invention, the drum is flxedly mounted on and for rotation with a rotatable shaft having a smooth portion extending ,through the drum and a threaded end portion extending outside the drum at one end thereof. A reciprocable press platen is mounted on the smooth shaft portion adjacent the threaded end portion while a fixed drum bottom is mounted near the opposite end of the shaft. The

'threaded shaft end is engaged by a threaded bearing supporting this end and held in fixed relationship to the press platen while the other shaft end is rotatably journaled in another bearing, one of said bearings being movable in relation to the other bearing to permit reciprocation of the press platen when the shaft is turned.

An advantage of using a single reciprocable press platen lies in the fact that drum and shaft may be rather short since the fixed bottom serves as the second press platen. Also, when shaft and drum rotate together, there is no radial friction between shaft and press material, and between shaft and protective sleeve, if such is used.

According to another embodiment of the invention, a press drum with one open end is fixedly mounted with its closed end on a rotatable shaft. A reciprocable press platen is mounted in the open drum end and has an outwardly extending threaded shaft supported in athreaded bearing, means being provided for rotatably supporting the open drum end on said threaded bearing. This press has no shaft at all in its press chamber, thus obviating any possibility of jamming of the mass on a shaft in the chamber.

In yet another embodiment, a fixed shaft extends through the press drum and has two threaded end por tions extending from respective ends of the drum. The drum is rotatably supported on the shaft and two rams are reciprocably mounted on the shaft inwardly of the threaded end portions and engage these portions with nuts fixed to the rams. To enable the rams to approach each other and to move away from each other while being rotated in the same direction, one of the end portions of the shaft has a left-hand thread while the other one has a right-hand thread.

ln the embodiments of the press wherein the shaft ex.- tends through the press chamber, the smooth shaft'por` tion in the chamber may be covered with an elastic sleeve with end anges hermetically sealed to the press platens. lf desired, a fiuid may be introduced into said sleeve to exert a radial pressure on the pressed material while the press platen or platens are actuated.

In accordance with another feature of the invention, a limit switch arrangement may be provided to stop the rotation of the drum when the reciprocable press platen has reached a predetermined end position. Also, if

desired, means may be provided for controlling the maxi-V Fig. 2 is a similar section through another embodiment of the press;

Fig. 3 is a similar section through a third embodiment of the press;

Figs. 4 and 5 are vertical cross sections of Figs. l and 2, respectively;

Fig, 6 is an end view of the press of Fig. 3, as viewed from the left of this figure;

Fig. 7 is a section showing a limit switch arrangement applied to the press of Fig. 3;

Fig. 8 is anend View of Fig. 7; and

Fig. 9 is a section showing a pressure control arrange- Vment for the press of Fig. 3.

Referring now to the drawing, wherein like reference numerals indicate like parts in all embodiments, Figs. 1 and 4 show a press with two reciprocable press platens or rams'mounted on a fixed shaft.f The support frame 1 carries shaft bearings 3 and 4. The two ends of shaft 2 are keyed in the bearings so that the shaft is fxedly held therein against rotation. Cylindrical drum 5 defines the press chamber and consists, in the illustrated embodiment, of wooden slats 6 held together by steel rings 8, longitudinal slots 7 (see Fig. 4) being left between adjacent slats. As will be appreciated by` the skilled in the art, this type of pressure chamber wall may be replaced, for instance, by a tubular steel sieveor any equivalent perforate wall means. Frusto-conical spiders 9 are connected to the two ends of drum Sand carry hubs 10. The xed shaft 2 is journaled in central Vbores of hubs 10 so that the drum is rotatably mounted on the shaft. The shaft end adjacent bearing 3 is provided with a righthand thread 11 and the shaft end adjacent bearing4 has a left-hand thread 12, the respective threads extending inwardly from near the spider hubs to about the respective ends of the drum.

Theends of drum 5 are closed by pressure platens or rams 13 and 14 journaled on fixed shaft 2, the central bores of the platens being sealed by annular gaskets 15. The pressure platens carry cylindrical bushings 16 which surround the shaft threads 11 and 12. With their threaded end walls 18, the bushings form nuts which permit a translating or reciprocatory movement of the platens on the shaft. Stiffening ribs 17 provide additional support for the bushings 16 on platens 13 and 14. The platens have substantially the same diameter as the press chamber in the drum and are so mounted on the shaft threads that they form end closures for the press chamber in the end or non-operating position of the platens.

As shown in Fig. 4, a plurality of circumferentially spaced guide rails 19 are arranged in the drum wall and theplatens have corresponding notches 20 for sliding engagement with the guide rails during the reciprocating movement of the platens along the shaft 2, as will be hereinbelow explained.

Motor 21 is mounted on the press support frame 1 and is connected by a belt to pulley 22 (see Fig. 4) carrying shaft 23 and pinions 24 which engage annular racks 25 mounted at the respective ends of the drum 5. When the motor is actuated and pinions 24 are rotated, their engagement with racks 25 causes rotation of the drum on the fixed shaft. The guide rails 19, engaging notches 20 in the pressure platens 13 and 14, force the pressure platens to rotate with the drum and, due to the fact that the platens reciprocate on left-hand and right-hand threads, respectively, the platens will either approach each other or move away from each other during rotation, depending on the direction of rotation.

As shown in Fig. 4, the drum has a feed and discharge opening intermediate its ends for the introduction of material to be pressed and the discharge of the pressed material, the opening being closable by door 26. A receptacle 27 is placed below the drum to receive liquid extracted or pressed from the charge in the press chamber and leaving the chamber through slots 7 of the drum wall. The receptacle is preferably mounted on rollers or wheels 32 to facilitate its handling and, of desired, theserrollers may run on rails.

Cords, wires or strings 28 of synthetic material or the like extend between the pressure platens and have their ends attached thereto. These elongated exible elements serve to facilitate the breaking of the pressed mass when the platens are moved apart after the compression stroke and the elongated elements are thereby tautened and cut through the pressed mass or cake.

The operation of the press is obvious from the above description of its structure.

Before a pressing operation, the drum is rotateduntil the pressure platens or rams 13 and 14 take their initial position at the ends of the drum 5, as shown in Fig. 1. The door 26 is then opened and the drum is charged with the material whose liquid content is to be extracted. After closing the drum door, the motor 21 is switched on and the drum is rotated so that the two pressure platens move in the drum toward each other. During this cornpression stroke of the platens, the material in the press chamber is compressed and liquid contained in theV material is squeezed out of the material and discharged through slots 7 in the drum wall into receptacle 27. When it is desired to terminate the compression stroke, the direction of rotation of motor 21 is reversed so that the two rams execute a reversed translating movement until they return to their initial position. This movement of the rams causes the cords 28 to be tautencd and thus to tear or break apart the pressed mass in the drum. The broken pieces of the pressed mass are further comminuted by the rotation of the drum so that the mass is prepared for a further pressing operation. This is of particular advantage if the material is a fruit mash whose juice should be carefully yet sufficiently extracted. After repeated pressing and when it is determined that all use iul liquids have been extracted from the material, the ptatens are returned into their initial position, the door E6 is opened or removed and the drum may be rotated with its opening facing down so that the particulate residue in the press chamber may be emptied into a receptacle piaced underneath the drum 5.

Figs. 2 and 5 illustrate a press with a single reciprocable press platen or plunger mounted on a rotatable shaft. Drum 5 constituted by slats 6 held together by rings S is similar to the drum of the above-described embodiment. The drum has one end closed by fixed bottom 2?. The drum bottom has a central hub 29a keyed `to shaft 2' so that the drum bottom and the drum are fixedly connected with the shaft and rotatable therewith. Stiifening ribs 17' reinforce the connection between the drum bottom and its hub.

The support frame for the press comprises rolling horses 3' and 4 which carry the bearing means for the ends of the shaft. The end 36 of` shaft 2' is rotatably journaled in bearing 42. The other end of the shaft has a threaded portion 11' extending to a point adjacent to but outside the end of the drum 5. The threaded end portion of the shaft is mounted in a nut bearing 13' on horse 4'.

A reciprocable press platen or plunger 14 is mounted on the smooth portion of the shaft 2', the central bore of the platen being sealed by gasket 15. The platen carries sleeve 16', stiffening ribs 17 providing additional support for the sleeve which surrounds the threaded shaft portion 11'. End plate 31 is iixedly connected to sleeve 16'. for instance by welding. Also tixedly mounted on the sleeve 16' is sprocket 31. A split follower ring 33 is bolted to the end plate 31 by screws 35 and has a ange engaging the shoulder 34 of nut 18. In this manner, the platen 14', sleeve 16', end plate 31, pinion 31' and follower ring 33 constitute a xedly connected plunger unit. A thrust bearing 36 is mounted between end plate 31 and nut 18', being held in position by follower ring 33.

As in the embodiment of Figs. 1 and 4, the press platen is held against rotation in respect of the drum by guide rails 19 engaging notches 20 in the platen. When motor 21 is actuated and turns sprocket 47, which is connected by chain 48 with sprocket 31', the plunger unit is rotated and the rotational movement is transmitted to the drum by means of the guide rails 19 connecting the press platen with the drum. Since the shaft 2' is xedly connected with the drum, it is simultaneously rotated. When the motor is turned in a direction causing the threaded shaft portion 11' to be screwed into nut 18', the press platen 14 will be forced toward the xed drum bottom 29 While the thrust bearing 36 absorbs theA friction between turnning endlrplate` 31 andstationary n ut 1,8'. When the motor is turned in the other direction, the press platen will move gaseosa away from the xed drum bottom because the follower ring 33 prevents relative axial movement of the end plate 31 and press platen 14 from the nut 18.

The bearing support horses 3' and 4 are mounted on wheels 37 so that they may readily participate in the reciprocating movement of the drum 5 and press platen 14', respectively. For practical purposes, however, it will be preferred 'to iix the position of one of the horses so that only one end of the press may make the translating movement. In the illustrated embodiment, brake shoes 45 and 46 are provided to immobilize the rollers 37 of horse 4 so that the reciprocating movement will be effected only yby horse 3 and the drum while platen 14 will remain stationary.

If receptacle 27 is provided with lwheels 32, it will be of advantage to place the mobile parts of the Press on a frame 38 carrying U-shaped rails 39, the outer legs 40 of the rails carrying the rollers 37 of the horses 3 and 4 while the rollers 32 of the receptacle run on inner legs 41 ofthe rails. Receptacle 27 is connected and movable with horse 3 by means of a hook 43 engaging lug 44 mounted at one end of the receptacle.

All other parts of the press are the same as in the embodiment of Figs. l and 4, the operation also being similar thereto, as will be readily appreciated from the previous description of the operation and the structural differences of the embodiment of Figs. 2 and 5. The basic difference resides in the fact that, while two press platens move toward each other relative to the drum in the first-described embodiment, only one press platen moves against a stationary drum bottom in the second embodiment, the compression stroke of the plunger unit being effected by turning the threaded shaft portion into the nut bearing while the plunger is moved out of the drum toward the end position shown in Fig. 2 by reversing `the direction of rotation of the motor.

Another embodiment of a press with a single plunger is illustrated in Figs. 3 and 6. The drum 5 with its fixed bottom 29 is similar to the drum of Fig. 2 and like reference numerals designate like parts therein. The reciprocable plunger unit of the press comprises press platen 13' mounted on threaded shaft 2". Shaft butt 30 is keyed to drum bottom 29 and rotatably journaled in bearing 42 on stationary horse 1. The shaft butt is held in its bearing against axial movement. Stationary horse 1 on the opposite end of the drum carries nut Vbearing 3" threadedly receiving the plunger shaft 2". The adjacent end of the drum has mounted thereon spider 9 which is rotatably mounted on a collar of the nut bearing 3" by means of hub 101.

The drum walls in this embodiment are subjected to considerable pressure and, therefore, I have provided a plurality of circumferentially spaced longitudinal stiftening bars 17 mounted over the retaining rings 8 to give added strength to the drum walls.

The drum is rotated by any suitable means (not shown), such as a chain and sprocket drive as used in the embodiment of Fig. 2, one sprocket being mounted, for instance, either between bottom 29 and bearing 42 on shaft butt 30 or on an extension of the shaft butt beyond the bearing. If desired, the drum may carry an annular rack, such as shown in Fig. l, for driving connection with a reversible motor. Since many suitable drives will readily occur to the skilled in the art and specific drives have been illustrated by way of example in Figs. l and 2, Fig. 3 has not been encumbered with such an illustration for the sake of clarity and to direct more particular attention to the subject matter of the invention. Also, the description of those parts of the press also shown in the other embodiments is not repeated.

Since, as in the other embodiments, the press platen 13 is keyed Ito the drum to be rotatable therewith, rotation of the drum will cause the plunger to move into or out-f the drum, depending on the direction of rotation,

6 the threaded shaft 2' being correspondingly screwed into or out of its nut bearing.

Figs. 7 to 9 illustrate arrangements for the actuation of a limit switch and actuation or stoppage of the drive motor in dependence on the pressure in the press chamber. The arrangement of Figs. 7 and 8 is applied to the embodiment of Fig. 3, like reference numerals designating like parts in these figures.

As shown, horse 1 carries limit switch 52 which has a switch lever '53 actuatable by rods 49, three such rods being used in the illustrated embodiment. Longitudinal switch actuating elements or rods 49 are mounted on the press platen 13 and extend toward switch lever 53 through spider 9. Their length is such that they will engage and depress the switch lever when the drum is rotated and the press platen is in its end position (indicated in Figs. 3 and 7). When the switch is actuated by depression of the switch lever, the motor stops so that the drum is` prevented from further rotation when the press platen reaches the end of the drum. The desired stop position may be adjusted by making the length of the rods adjustable. In the illustrated embodiment, the rods 49 are threadedly mounted in support sleeves 50 and may be held in their adjusted position by lock nut 51.

A single switch actuating rod would suiice, of course, to stop the motor but a plurality of rods are provided as a safety factor. In this manner, the motor will be very promptly stopped again if it was mistakenly started to run in the wrong direction after it has been stopped in the end position of the press platen instead of being reversed for the compression stroke of the platen. Otherwise, the platen would be moved so far out of the drum that it may be jammed in the drum spider, thus damaging the press. When several switch actuating rods are arranged about the platen, a wrong turn of the motor in the end position of the platen will stop the motor after a quarter or a third of a turn, for instance, Vrather than a full turn, as would be the case with a Vsingle rod.

With most materials to be pressed, itis important to control the maximum pressure in the press chamber. A pressure control arrangement for this purpose is illustrated in Fig. 9, the illustrated embodiment of the pressure control means being shown in conjunction with the press of Fig. 3.

As shown, the drum bottom 29 and shaft butt 30 have a bore 56 communicating with the interior of the drum. An elastic membrane 54, for instance of rubber or a like elastomer, is mounted on the interior wall of the drum bottom by means of a retaining ring 55, the diameter of the membrane being such that it covers bore 56k and defines an hydraulic pressure chamber in the drum, which is hermetically sealed from the press chamber. A conduit pipe 57 connected to pipe 59 is mounted in bore 56 so that a tiuid medium may be supplied into the pressure chamber of the drum from the outside through pipes 59 and 57. Valve 61 in pipe 59 may be operated to supply uid, such as water, to the pressure chamber or to shut the fluid supply off. Relief valve 60 is provided to prevent an undesirably high pressure to be exerted against the membrane 54 when the pressure chamber is initially filled to produce a desired initial pressure therein. A Contact manometer is mounted in the fluid supply conduit, i.e. in pipe '59, with an electric conductor leading to the motor switch. A fluid discharge conduit 62 is mounted in the drum bottom in communication with the pressure chamber of the drum, a relief valve 63 being mounted on the discharge conduit.

'I'he press chamber pressure control arrangement just described operates as follows:

At the beginning of the press operation and before initiation of the compression stroke, the valve 61 is opened and a liquid is introduced into the pressure chamber of the drum under a predetermined pressure to extend the membrane S4 into the position 54 (indicated in broken lines). The resiliency of the membrane is preferably so chosen that it will be approximately hemispherically extended under a relatively low pressure below the pressure exerted in the press chamber during the compression stroke of the press platen. For instance, a pressure of about 0.25 kg./cm.2 may suflice for this purpose. The liquid introduced into the pressure chamber will force any air therein out of the chamber through the reliefV valve 63. When the material charged into the press chamber is forced against drum bottom 29 and membrane 54 during the compression stroke of the press platen, the compression force will be transmitted to contact manometer 58 as soon as it rises above the initial pressure in the pressure chamber. The manometer is adjusted to a desired maximum pressure value and as soon as this value is reached in the press chamber, the manometer will automatically effectuate stoppage of the motor in a manner well known per se. The manometer may again automatically switch on the motor if the pressure in the pressure chamber sinks below a predetermined level, for instance by removing liquid therefrom. Y

While I have described the invention in connection with certain preferred embodiments, it will be obvious that `many changes and modifications may be effected in the structure, particularly after benetitting from the present disclosure, without departing from the spirit and scope of this invention as defined in the appended claims.

What is claimed is:

l. A press for extracting moisture from a moisture-containing material, comprising rotatable perforate drum means having an axis and radially defining a press chamber, horizontally extending shaft means rotatably supporting said drum means and having a threaded end portion totally outside said chamber, two press platensV mounted on the shaft means to constitute press chamber bottoms, at least one of said press platens being mounted on shaft means for reciprocatory axial movement in a direction inward and outward of said chamber, a threaded bearing engaging said threaded shaft end portion, the threaded shaft end portion and the threaded bearing constituting two elements axially reciprocable relative to each other and the reciprocable press platen being tixedly connected to one of said elements whereby the reciprocable platen may be axially reciprocated in relation to the other one of said elements and the other platen by turning one of said elements, a stress transmitting member for transmitting axial tensile stresses to one of said means when said platens are moved toward one another against the resistance of a material being extracted in said press chamber, follower means for securing said reciprocatory platen against rotation relative to the drum means, and means for rotating said drum means.

2. The press of claim 1, wherein said drum rotating means comprises an electric motor and al limit switch arrangement for stopping said motor, the limit switch arrangement including a switch and at least one switch actuating element mounted on said reciprocatory press platen and extending therefrom toward the switch for actuating the switch when the reciprocatory press platen is in a predetermined position, actuation of the switch causing stoppage of the motor.

3. The press of claim 2, wherein a plurality of radially spaced switch actuating elements are mounted 0n the reciprocatory press platen and longitudinally extend toward said switch, and means are provided for adjusting the length of each of said elements.

4. The press of claim l, wherein said drum rotating means comprises an electric motor, the press further comprising an arrangement for controlling the maximum pressure in the press chamber, said arrangement including an elastic membrane mounted on at least one of said press platens in the press chamber to define a hydraulic pressure chamber, liquid conduit means in said press platen leading from the outside of the press chamber into said hydraulic pressure chamber, a relief valve means communicating with the hydraulic pressure chamber to permit the discharge of air therefrom upon supply of liquid thereinto through said liquid conduit, a valve in said liquid conduit for closing the conduit after the liquid has been supplied to the hydraulic pressure chamber, a contact manometer in said conduit and responsive to the pressure in said pressure chamber, and electric circuit means connecting the contacts of said manometer with the electric motor whereby the motor may be switched off when the manometer registers a predetermined maximum pressure.

5. A press for extracting moisture from a moisturecontaining material, comprising a rotatable perforate drum radially defining a press chamber, means for rotating said drum, a fixed bottom secured to and axially closing one end of the drum, a first horizontally extending shaft keyed in said bottom, a first shaft support with a bearing wherein the first shaft is rotatably journaled, a second horizontally extending and externally threaded shaft, a second shaft support including an internally threaded bearing engaging the threaded shaft, means for rotatably sup` porting the other end of the drum on the latter bearing in axially secured relationship, a reciprocable press platen fxedly connected to an end of the threaded shaft in said drum whereby the platen may be axially reciprocated in said press chamber by turning the threaded shaft in said threaded bearing, and follower means for securing said reciprocable platen against rotation relative to the drum` whereby during operation of said press said drum is stressed in axial tension counteracting the radial outward pressure of the moisture containing material therein, and said threaded second shaft is stressed in axial compression, and all stresses developed during operation are contained by said shaft and said drum independent of the supports.

References Cited in the iile of this patent UNITED STATES PATENTS 293,603 Thompson Feb. l2, 1884 903,574 Hupfel Nov. 10, 1908 FOREIGN PATENTS 1,122,632 France May 28, 1956 

